Power supply



FIG. 1 is a perspective view of a power supply showing our new design thereof; FIG. 2 is a right side elevational view thereof; FIG. 3 is a top plan view thereof; FIG. 4 is a front elevational view thereof; FIG. 5 is a bottom elevational view thereof; FIG. 6 is a left side elevational view thereof; and, FIG. 7 is a rear elevational view thereof. 

The ornamental design for power supply, as shown and described. 